Connector with interchangeable contacts

ABSTRACT

A connector is described wherein some contacts include circuit components, and the contacts can be arranged in a custom pattern by the user. A first group of component contacts (e.g. 22A, FIG. 4) each includes at least one circuit component (60) mounted on the middle of a conductive element (52A), with the contact having a cylindrical conductor (64) of predetermined outside diameter D. A second group of passive contacts include a feed through contact (22C, FIG. 6) wherein insulation (80) is disposed about the middle of a conductive element and has about the same outside diameter as the component contacts to enable the contacts to be interchanged. The connector include a ground plane (40, FIG. 3) with holes through which each contact passes, and with fingers at the holes for engaging the outside of each contact. The ground plane can be part of a holder (14, FIG. 3) which includes forward and rearward insulators (90, 92) with one having tabs that project through slots in the ground plane and in the other insulator. An assembly can include two substantially identical connectors (132, 134, FIG. 9) in tandem, with the contacts of each connector connected in tandem with the contacts of the other connector, to provide more complicated and custom designed contact circuitry.

BACKGROUND OF THE INVENTION

Connectors designed for avionics, military, and other high performanceapplications, have recently included contacts with circuit components.For example, contacts have been used which include Zener diodes or metaloxide varistors (MOV'S) for dissipating to ground, high energy pulsesthat may be induced on the contact. Other contacts have been designedwith filters such as pi filters (an inductor between two capacitors)that block signals above a predetermined frequency such as highfrequency noise. Although a connector user can specify to themanufacturer the particular type of connector he requires, specifyingwhich type of component contacts lie at particular locations, this makesit difficult for the user to try different configurations and requiresthe manufacture to custom make each different type of connector. If thecustomer, or user, could easily produce his own connector from suppliedparts, this could reduce the manufacturing costs and increase theability of the user to modify his own connector.

Ground planes currently used in connectors to ground some of thecontacts, can include a thin plating on an insulator or a sheet metalground plane. The plated ground plane cannot carry high current surgesand the plating cost is considerable. Current sheet metal ground planesare bonded to insulators to assure that the spring fingers at the outeredge of the ground plane will lie stably within a connector shell. Thecost of bonding the sheet metal ground plane to an insulator adds to thecost of the connector. A ground plane and insulator assembly which couldbe constructed at low cost would be of value.

SUMMARY OF THE INVENTION

In accordance with one embodiment of the present invention, a connectoris provided of the type that has at least one component contact whichincludes a component mounted on a conductive element, which is versatileand of low cost. The connector is of the type that includes a groundplane with contact-passing apertures through which a contact can beinserted so a middle portion of the contact is connected to the groundplane. A first group of contacts comprise component contacts, eachincluding a circuit component mounted on the middle of the conductiveelement and a cylindrical conductor of a diameter to engage ground planefingers in the ground plane aperture. A second group of contactscomprise feed through contacts, each including insulation surroundingthe middle of the element, with the insulation having a largelycylindrical exterior of a diameter great enough to engage fingers of theground plane. A third group of contacts comprises ground contacts, eachincluding an enlarged conductive element middle diameter great enough toengage fingers of the ground plane. The feed through and ground contactsare interchangeable with the component contacts.

The ground plane is stamped or otherwise formed of a sheet of metal andhas slots. Forward and rearward insulators lie facewise against oppositefaces of the ground plane, with one insulator having tabs that projectthrough the slots in the ground plane and into slots in the otherinsulator where the tabs are tightly captured to hold the assemblytogether.

A pair of connectors with interchangeable contact can be connected intandem, with each contact of one connector lying in tandem with acontact of the other connector. This enables each pair of tandemcontacts to provide a more complicated circuit, as where one provides adiode for dissipating most of the energy of a pulse, and the otherprovides a filter for further dissipating the pulse energy at certainfrequencies.

The novel features of the invention are set forth with particularity inthe appended claims. The invention will be best understood from thefollowing description when read in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front isometric view of a connector constructed inaccordance with the present invention.

FIG. 2 is a front elevation view of the connector of FIG. 1.

FIG. 3 is a view taken on the line 3--3 of FIG. 2.

FIG. 4 is a sectional view of the diode contact of FIG. 3.

FIG. 5 is a sectional view of the filter contact of FIG. 3.

FIG. 6 is a sectional view of the feed through contact of FIG. 3.

FIG. 7 is a sectional view of the ground contact of FIG. 3.

FIG. 8 is an exploded isometric view of the holder of FIG. 3.

FIG. 9 is a partial sectional view of a connector arrangementconstructed in accordance with another embodiment of the invention.

FIG. 10 is a sectional view of a varistor contact which can be installedin the connector of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 3 illustrates a connector 10 which includes a conductive shell 12and a holder 14 lying within the shell. The holder has forward andrearward ends 16, 18 and a plurality of contact-receiving holes 20. Aplurality of contacts 22A-22D lie in each of the holes, with eachcontact having forward and rearward ends 30A-30D and 32A-32D. Eachcontact has a middle portion such as 34D lying between the opposite endsof the contact.

The holder 14 includes a conductive ground plane 40 extending across theinside of the shell 12, and having a radially outer edge portion 42forming multiple tangs 44 that engage the inside of the shell, so theshell and ground plane are at the same potential (usually groundpotential). The ground plane has a plurality of apertures 46 lying atthe contact-receiving holes 20 of the holder, and has a plurality ofprojecting fingers 48 at each aperture. The projecting fingers extendinto the aperture, and engage the middle portions 34A-34D of thecontacts. The fingers are designed to engage contacts whose middleportions have an outside diameter D within a predetermined range ofdiameters. The middle portions of all of the contacts preferably have anoutside diameter within this range.

Each of the contacts is installable in any of the plurality ofcontact-receiving holes. Each of the contacts can be removed andinstalled in the hole previously occupied by another contact, so thecontacts are interchangeably installable in any of the holes. Rearrelease retainers 49 hold each contact in place.

FIGS. 4-7 illustrate details of each of the four contacts 22A-22D. Allof the contacts include a conductive element 52A-52D extending along theentire length of the contact. The forward ends 30A-30D and rearward ends32A-32D of each of the conductive elements and contacts are preferablythe same, but the element middles 54A-54D may be different for differentcontacts.

FIG. 4 illustrates a diode contact 22A which includes a Zener diode 60mounted on a platform 62 formed in the element middle 54A, with oneterminal of the diode mechanically and electrically connected to theplatform 62. The contact also includes a ground clip 64 with an outerpart 68 lying at the outside of the contact middle portion 34A on adiameter D. The clip 64 has an arm 66 that extends inwardly to aterminal of the diode 60 that is opposite the contact element platform62. A quantity of molded insulation 69 surrounds the element middle 54Aof the conductive element 52A. The purpose of the insulation is toprotect the diode 60 from mechanical damage and to form a cylinder withdiameter D. When a high voltage pulse travels along the contact, theZener diode breaks down and allows most of the energy of the pulse topass through the ground clip 64 and through the ground plane engagedtherewith to ground. This type of diode contact 22A has been sold byapplicant for several years.

FIG. 5 illustrates the filter contact 22B. It includes a ferrite bead 70surrounding the element middle 54B of the conductive element 52B, and apair of capacitors 72, 74 surrounding the element middle and lying atopposite ends of the ferrite bead. A conductive cylinder 74 surroundsthe ferrite and capacitor circuit components. Each capacitor has aninner terminal electrically connected to the conductive element middleand the outer terminal connected to the conductive cylinder 74.Applicant prefers to use discoidal capacitors, which have conductiveplates extending perpendicular to the length of the conductive element.It may be noted that the ferrite bead 70 does not have to beelectrically connected to anything, and preferably does not touch theconductive cylinder 74 to avoid a moderate resistance direct connectionof the conductive element and conductive cylinder through the ferritebead. It may be noted that both the diode contact 22A and filter contact22B may be considered to be component contacts in that each includes acircuit component. A circuit component is a device such as a diode,capacitor, inductor, varistor or resistor that affects changing currentspassing therethrough, other than merely always conducting or always notconducting them. The circuit component can be any shape such as a chipdiode or a tubular varistor.

FIG. 10 illustrates a varistor contact 22E which can sometimes be usedinstead of the diode contact of FIG. 4 to dissipate high energy pulses.The varistor contact 22E includes a circuit component formed by avaristor 75 mounted on an element middle 54E. The tubular varistor hasbeen metalized, so it has metal layers 76, 78 at its inner and outerdiameters. The inner layer 76 contacts the element middle 54E while theouter layer 78 contacts fingers of the ground plane when the varistorcontact is installed in the connector.

FIG. 6 illustrates the feed through contact 22C which includes aquantity of insulation 80 surrounding the element middle 54C of theconductive element 52C. The radially outer surface 82 of the insulationis substantially cylindrical, and has about the same diameter as theoutside diameters of the ground clip 64 and conductive cylinder 74 ofthe contacts of FIGS. 4 and 5. The purpose of the insulation 80 is toisolate the conductive element 52C from the fingers of the ground planeto avoid contact with the ground plane. The outer diameter of theinsulation 80 is preferably large enough to engage the fingers of theground plane that extended to the aperture through which the feedthrough contact extends. This enables the fingers of the ground plane tostabilize the position of the middle of the feed through contact andprevent it from "rattling". In addition, this allows a mold used to moldinsulation at the middle portion 34A of the diode contact, to be used tomold the insulation at the middle portion 34C of the feed throughcontact.

FIG. 7 illustrates details of the ground contact 22D. The middle portion34D of the ground contact is formed by an enlarged element middle 54D ofthe conductive element 52D. The ground contact can be used to connectthe ground plane and thereby the shell of the connector, to ground, incases where there is not another grounding system to connect to theshell of the connector. The middle portions of all of the contact22A-22D preferably have approximately the same outside diameter D.

FIG. 8 illustrates details of the holder 14 which holds the contacts inplace. The holder includes forward and rearward insulators 90, 92 havinginner surfaces 94, 96 facing each other. The ground plane 40 is aconductive sheet, formed of sheet metal that has been stamped, formed,heat treated and gold plated prior to assembly. The ground plane 40 issandwiched between the inner surfaces 94, 96 of the insulators. Theground plane is formed with a plurality of slots 100-104. The rearinsulator 92 also has a plurality of slots 106-110 aligned with theslots in the ground plane. The forward insulator 90 has a plurality oftabs 112-116 that project through the slots in the ground plane 90 andinto the slots in the rearward insulator 92. The tabs 112-116 arecaptured in the rearward insulator slots 106-110, as by heat weldingthem in place, providing for an interference fit of the tabs in theslots, or providing latches. When the holder 14 is assembled, it can beinserted as a unit into the shell, with the ground plane 40 stabilizedin position to assure that as its fingers 44 press against the inside ofthe shell, the ground plane will extend perpendicular to the shell.

Referring again to FIG. 3, it can be seen that the connector includes aninterfacial seal 120 at the front of the holder for sealing around thefront ends 30A-30D of the contacts, and includes a peripheral seal 122around the interfacial seal. A grommet 124 lies at the rear of theholder and has multiple openings 126 that can pass wires 128 thatconnect to the rearward ends of the contacts. The particular contactsshown have cylindrical bores 144 (FIG. 4) in their rearward end, thatcan be used to receive the conductors of wire and which can be crimpedto the conductors.

FIG. 9 illustrates a connector assembly 130 which includes twoconnectors 132, 134 connected in tandem, with each connector beingsimilar to the connector of FIG. 3. The second connector 134 and itsparts may be referred to as "devices" to distinguish them from the firstconnector 132 and its parts. The connectors have adjacent flanges 136,138 with holes for receiving screws 140 that hold the shells together. Afirst contact 22A in the first or forward connector 132 is a diodecontact which has the construction shown in FIG. 4. However, thecylindrical bore 144X has been slotted to form fingers that have beendeformed to converge slightly and form a socket, so as to receive andengage the pin-like forward end such as 30B of another contact. A firstcontact 22B in the second or rearward connector 134 is a filter contacthaving the construction of the contact shown in FIG. 5. The forward end30B of the filter contact engages the socket in the diode contact 22A.Thus the connected contacts 22A, 22B provide both a Zener diode fordissipating much of the power of a high voltage pulse, while filtercontact 22B can further dissipate the pulse at certain frequencies. Inanother example, the low pass filter at position 22B can be connected intandem with a high pass filter in the other connector, to therebyproduce a band pass filter. The manufacturer supplies the parts of thearrangement and the user can install the contacts, with the tandemarrangement enabling the contacts to provide more complex circuitry andwith greater versatility than heretofore.

A variety of other active contacts can be provided, including those withjust a capacitor, ferrite bead, resistor, or varistor. This providesconsiderable versatility in designing a circuit in the connector formodifying currents that may pass through a wire 128 to the connector.

Thus, the invention provides a connector which enables high versatilityfor the user, at moderate cost. The connector includes a holder within aconductive shell, the holder including a ground plane with finger ateach aperture therein for engaging contacts. A variety of contacts areprovided, including groups of component contacts (each group includes atleast one contact) having one or more circuit components, and groups ofpassive contacts such as a feed through contact having a substantiallycylindrical insulator surrounding the conductive element of the contact,with the outside of the insulator being large enough to engage fingersof the ground plane. The holder can include a sheet metal ground planesandwiched between a pair of insulators, with one of the insulatorshaving tabs projecting through slots in the ground plane and in theother insulator and captured in the other insulator to hold the partssecurely together as a unit. A contact arrangement can be used whichincludes two similar connectors with interchangeable contacts to providefor more complex circuitry along each pair of contacts.

Although particular embodiments of the invention have been described andillustrated herein, it is recognized that modifications and variationsmay readily occur to those skilled in the art, and consequently, it isintended that the claims be interpreted to cover such modifications andequivalents.

I claim:
 1. A connector which has a conductive shell, a holder lying insaid shell with said holder having forward and rearward ends and aplurality of contact-receiving holes therein, and a plurality ofcontacts each lying in one of said holes with each contact havingforward and rearward ends lying adjacent to corresponding ends of saidholder and with each contact having a middle portion, wherein saidholder includes a conductive ground plane extending across the inside ofsaid shell and having an outer edge portion electrically grounded tosaid shell and a plurality of apertures lying at said contact-receivingholes and having projecting fingers extending into said apertures forengaging said contacts with said finger formed to engage a cylindricalportion of predetermined diameter, characterized by:each of saidplurality of contacts is individually removable and replaceable and isinterchangeably installable in any of said plurality ofcontact-receiving holes, and each of said plurality of contacts includesa conductive element extending along the entire length of the contactand having an element middle; a first group of said contacts includingcomponent contacts with each including a circuit component mounted onsaid element middle and a substantially cylindrical conductor of saidpredetermined diameter extending about said element middle, saidcomponent having a first terminal connected to said element middle and asecond terminal connected to said cylindrical conductor; a second groupof said contacts including a feed through contact having only insulationsurrounding the element middle.
 2. The connector described in claim 1wherein:said insulation on said feed through contact middle has asubstantially cylindrical exterior which is of substantially saidpredetermined diameter.
 3. The connector described in claim 1wherein:said holder includes front and rear insulators with facing innerends and said ground plane includes a metal sheet that is sandwichedbetween said insulators, a first of said insulators having a pluralityof tabs extending from the inner end thereof toward the other insulator,and the second of said insulators having a plurality of slots extendinginto the inner end thereof and which are constructed to receive andcapture said tabs, said ground plane having a plurality of slots thatreceive said tabs.
 4. The connector described in claim 1 including:asecond connector device having a second conductive shell device, asecond holder device lying in said second shell device with forward andrearward ends and a plurality of contact-receiving holes therein, and aplurality of second contact devices each lying in one of said holes insaid second holder device with each second contact device having forwardand rearward ends and a middle portion, wherein said second holderdevice is substantially identical to said holder and includes a secondconductive ground plane device with fingers for contacting said secondcontact device; said rear ends of said contacts form sockets and saidfront ends of said second contact devices form pins that can enter andmate with said sockets; said connector and said second connector deviceare fastened in tandem, with the pins of said second contact devicelying in said sockets of said contacts to connect them in tandem withone of said contacts and one of said contact devices which are connectedin tandem each including a circuit component.
 5. A connectorcomprising:a conductive shell; a holder lying in said shell, said holderhaving forward and rearward ends and a plurality of contact-receivingholes therein extending between said ends, said holder including aground plane having a plurality of apertures at the positions of saidholes and having a plurality of fingers projecting into each aperture; aplurality of contacts which are individually removable and replaceablein said holder holes, said contacts being interchangeably mountable ineach of said plurality of holes, with each contact having a conductiveelement with opposite ends and a middle, said plurality of contactsincluding at least one component contact and at least one passivecontact; said component contact having a circuit component with a firstterminal connected to said element middle and a second terminal, saidcomponent contact also having a conductive cylinder lying about saidelement middle and connected to said second terminal, said conductivecylinder being of a diameter to engage a plurality of said ground planefingers; said passive contact is devoid of a circuit component but has acontact middle with an insulative outer diameter large enough to alsoengage a plurality of said ground plane fingers.
 6. A connector assemblycomprising:first and second connectors that are connectable in tandem,each having a shell, a holder lying in the corresponding shell andhaving a plurality of contact-receiving holes and with said holderhaving a ground plane with apertures lying at each hole and with aplurality of fingers projecting into each aperture, and a plurality ofcontacts each mounted in one of said holes; each of said contactsincludes an elongated conductive element with first and second oppositeends forming first and second ends of said contacts and with an elementmiddle lying within one of said ground plane apertures, said contacts ofeach connector being interchangeably mountable in any of said holes ofthe holder of that connector; at least a first contact of each connectorincluding a circuit component with a first terminal mechanically andelectrically connected to said element middle, and also including aconductor connected to said second terminal with said conductor having alargely cylindrical outside of a diameter to be engaged by a pluralityof fingers of said ground plane; said connectors being connected intandem, with said second ends of said contacts of said first connectorforming sockets and with said first ends of said contacts of said secondconnector forming pins received in said sockets of said contacts of saidfirst connector, and with said first contacts of each said first andsecond connectors being connected in tandem, whereby to enable a morecomplex circuit to lie along a pair of tandem-connected contacts.
 7. Theconnector described in claim 6 wherein:said first contact of one of saidconnectors includes a diode as its component, and said first contact ofthe other connector includes a plurality of components forming a lowpass filter.